A Clear New Day
What is a Cataract?
Within the eye, an optical system exists which serves to focus light rays on the back of the eye. As light enters the eye, it is sequentially focused by the cornea (the clear dome in the front of the eye) and then by the lens, a clear structure like a "grape" with a skin and a soft interior located behind the colored iris. The light then goes on to image on the back of the eye (on the retina), which functions in a similar manner to the film in a camera.
Although the popular conception of cataract formation is a "growth" of some kind, in fact the formation of cataract is a clouding of the natural lens that prevents light from passing through. Because this clouding occurs slowly, symptoms of blurred vision can often go unnoticed.
A cataract is a clouding of the lens of the eye that prevents light from properly reaching the back of the eye. This clouding can take several forms. In the normal aging process the lens gradually becomes yellowed, and when the coloration becomes dark enough, vision is compromised. This process is similar to the discoloration we see when a glass bottle is left in the sun for many years. Another form of cataract involves the formation of a film on the front or back surface of the lens, called anterior or posterior capsular opacification. This form of cataract can cause more rapid deterioration of vision and can cause severe glare, particularly at night.
What Causes Cataracts?
Cataracts are part of the normal aging process and in fact can form with no particular cause other than age. The ultraviolet light from sunlight encourages the development of cataract and can also be detrimental to the retina and trauma to the eyes can cause cataract, even years after the original injury. Diseases such as diabetes may cause cataract and inflammation or infection of the eye and even some medicine such as steroids can cause cataract.
The use of sunglasses and antioxidant vitamins like vitamin E can slow both cataract formation and other eye problems such as macular degeneration.
What are Cataract Symptoms?
Changes in vision due to cataract formation can occur slowly, over a period of years, or can occur within a few months. Common symptoms include:
- Painless blurring of vision such as problems reading street signs
- Difficulty or the need for more and more light when reading
- Glare and difficulty seeing at night, or light sensitivity during the day
- Double vision or distorted vision
- More frequent changes in eyeglass prescription
- Fading or yellowing of colors
When Should Surgery be Done?
There is no universal answer to this question. If your vision is compromised: if you do not see well enough to do your job, drive at night, read the computer screen or watch TV, then you should consider cataract surgery. If cataract formation interferes with daily activities like cooking, shopping or reading the newspaper, then cataract surgery is appropriate. The need for surgery will be sooner for some than for others.
It is not true that cataracts need to be "ripe" before they can be removed. In fact, the longer cataracts form, the more difficult they become to remove, with higher potential risk of complications. Still, no urgency exists to remove the early to moderate cataract; the difference between today and a few months from now is only the visual loss accrued during that time.
Dr. Buzard will examine your eyes to determine the cause of your visual loss. The two of you will discuss how badly the problem is bothering you and whether cataract surgery is appropriate.
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